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Should each and every table have a primary key?
...most probably, you are missing something. Why keep identical records?
In MySQL, the InnoDB storage engine always creates a primary key if you didn't specify it explicitly, thus making an extra column you don't have access to.
Note that a primary key can be composite.
If you have a many-to-many l...
Foreign key from one app into another in Django
...end on each other and exist mainly to give me a convenient organisation of my files and namespaces. External apps (eg from DjangoPackages) and apps that I might one day contribute to the public, need to be kept as free as such dependencies as possible (although dependency on some other well-supporte...
Doing something before program exit
....org/library/atexit.html
For example, if I wanted to print a message when my application was terminating:
import atexit
def exit_handler():
print 'My application is ending!'
atexit.register(exit_handler)
Just be aware that this works great for normal termination of the script, but it won't...
How to create a GUID/UUID in Python
...tifies a machine uniquely on Windows, you can use this trick: (Copied from my answer at https://stackoverflow.com/a/58416992/8874388).
from typing import Optional
import re
import subprocess
import uuid
def get_windows_uuid() -> Optional[uuid.UUID]:
try:
# Ask Windows for the devi...
Rails has_many with alias name
In my User model I could have:
5 Answers
5
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The difference between Classes, Objects, and Instances
...You can use class House to create objects (instances of class House)
House myHouse = new House();
House sistersHouse = new House();
The class House describes the concept of what a house is, and there are specific, concrete houses which are objects and instances of class House.
Note: This is exact...
NGINX to reverse proxy websockets AND enable SSL (wss://)?
I'm so lost and new to building NGINX on my own but I want to be able to enable secure websockets without having an additional layer.
...
Bootstrap 3 and Youtube in Modal
I'm trying to use the Modal feature from Bootstrap 3 to show my Youtube video. It works, but I can't click on any buttons in the Youtube video.
...
How do I determine whether an array contains a particular value in Java?
...st(
new String[] {"AB","BC","CD","AE"}
));
(Paranoid people, such as myself, may feel more at ease if this was wrapped in Collections.unmodifiableSet - it could then even be made public.)
(*To be a little more on brand, the collections API is predictably still missing immutable collection type...
Regular expression to return text between parenthesis
...nthesis like that, you use rfind for the second part of the operation. See my post below for more details on this.
– FaustoW
Feb 17 '17 at 20:48
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